Viewing Graphic Symbol progress from a different timeline.

I am working on an animation. In the main timeline I have 2 graphic symbols on the stage, each has got its own timeline, and on it - its own animation.
When I am working inside Symbol A, as I progress in the timeline, Symbol B although visible, remains unchanged.

Is there a way in which I could work inside the timeline of Symbol A, and as I progress in A's timeline, watch the changes that occur in B's timeline ?

i haven't done this, so i am just talking off the top of my head, but if i needed to i would try it this way:

on a seperarate timeline/inside a movie clip, i would have my symbol 1( copy and paste all the frames from symbol 1) on the top layer(s) ( for example), and my symbol 2's frames on the bottom layer(s). now i can work on one, and see exactly where the other symbol is on any particular frame.

when done, gather up all the top layer(s) back into its own movie clip symbol, and do like wise to the bottom layer(s), so that now you have 2 seperate movie clips to use.